From: "Joel Fernandes (Google)" <joel@joelfernandes.org>
To: linux-kernel@vger.kernel.org
Cc: "Joel Fernandes (Google)" <joel@joelfernandes.org>,
Adrian Ratiu <adrian.ratiu@collabora.com>,
Alexei Starovoitov <ast@kernel.org>,
bpf@vger.kernel.org, Brendan Gregg <brendan.d.gregg@gmail.com>,
connoro@google.com, Daniel Borkmann <daniel@iogearbox.net>,
duyuchao <yuchao.du@unisoc.com>, Ingo Molnar <mingo@redhat.com>,
jeffv@google.com, Karim Yaghmour <karim.yaghmour@opersys.com>,
kernel-team@android.com, linux-kselftest@vger.kernel.org,
Manali Shukla <manalishukla14@gmail.com>,
Manjo Raja Rao <linux@manojrajarao.com>,
Martin KaFai Lau <kafai@fb.com>,
Masami Hiramatsu <mhiramat@kernel.org>,
Matt Mullins <mmullins@fb.com>,
Michal Gregorczyk <michalgr@fb.com>,
Michal Gregorczyk <michalgr@live.com>,
Mohammad Husain <russoue@gmail.com>,
namhyung@google.com, namhyung@kernel.org, netdev@vger.kernel.org,
paul.chaignon@gmail.com, primiano@google.com,
Qais Yousef <qais.yousef@arm.com>, Shuah Khan <shuah@kernel.org>,
Song Liu <songliubraving@fb.com>,
Srinivas Ramana <sramana@codeaurora.org>,
Steven Rostedt <rostedt@goodmis.org>,
Tamir Carmeli <carmeli.tamir@gmail.com>,
Yonghong Song <yhs@fb.com>
Subject: [PATCH RFC 3/4] lib/bpf: Add support for ftrace event attach and detach
Date: Wed, 10 Jul 2019 10:15:47 -0400 [thread overview]
Message-ID: <20190710141548.132193-4-joel@joelfernandes.org> (raw)
In-Reply-To: <20190710141548.132193-1-joel@joelfernandes.org>
Add the needed library support in this commit.
Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
---
tools/lib/bpf/bpf.c | 53 ++++++++++++++++++++++++++++++++++++++++
tools/lib/bpf/bpf.h | 4 +++
tools/lib/bpf/libbpf.map | 2 ++
3 files changed, 59 insertions(+)
diff --git a/tools/lib/bpf/bpf.c b/tools/lib/bpf/bpf.c
index c4a48086dc9a..28c5a7d00d14 100644
--- a/tools/lib/bpf/bpf.c
+++ b/tools/lib/bpf/bpf.c
@@ -24,6 +24,9 @@
#include <stdlib.h>
#include <string.h>
#include <memory.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
#include <unistd.h>
#include <asm/unistd.h>
#include <linux/bpf.h>
@@ -57,6 +60,8 @@
#define min(x, y) ((x) < (y) ? (x) : (y))
#endif
+#define TRACEFS "/sys/kernel/debug/tracing"
+
static inline __u64 ptr_to_u64(const void *ptr)
{
return (__u64) (unsigned long) ptr;
@@ -658,6 +663,54 @@ int bpf_raw_tracepoint_open(const char *name, int prog_fd)
return sys_bpf(BPF_RAW_TRACEPOINT_OPEN, &attr, sizeof(attr));
}
+int bpf_raw_tracepoint_ftrace_attach(const char *subsys, const char *name,
+ int prog_fd)
+{
+ char buf[256];
+ int len, ret, tfd;
+
+ sprintf(buf, "%s/events/%s/%s/bpf", TRACEFS, subsys, name);
+ tfd = open(buf, O_WRONLY);
+ if (tfd < 0)
+ return tfd;
+
+ sprintf(buf, "attach:%d", prog_fd);
+ len = strlen(buf);
+ ret = write(tfd, buf, len);
+
+ if (ret < 0)
+ goto err;
+ if (ret != len)
+ ret = -1;
+err:
+ close(tfd);
+ return ret;
+}
+
+int bpf_raw_tracepoint_ftrace_detach(const char *subsys, const char *name,
+ int prog_fd)
+{
+ char buf[256];
+ int len, ret, tfd;
+
+ sprintf(buf, "%s/events/%s/%s/bpf", TRACEFS, subsys, name);
+ tfd = open(buf, O_WRONLY);
+ if (tfd < 0)
+ return tfd;
+
+ sprintf(buf, "detach:%d", prog_fd);
+ len = strlen(buf);
+ ret = write(tfd, buf, len);
+
+ if (ret < 0)
+ goto err;
+ if (ret != len)
+ ret = -1;
+err:
+ close(tfd);
+ return ret;
+}
+
int bpf_load_btf(void *btf, __u32 btf_size, char *log_buf, __u32 log_buf_size,
bool do_log)
{
diff --git a/tools/lib/bpf/bpf.h b/tools/lib/bpf/bpf.h
index 9593fec75652..5b9c44658037 100644
--- a/tools/lib/bpf/bpf.h
+++ b/tools/lib/bpf/bpf.h
@@ -163,6 +163,10 @@ LIBBPF_API int bpf_prog_query(int target_fd, enum bpf_attach_type type,
__u32 query_flags, __u32 *attach_flags,
__u32 *prog_ids, __u32 *prog_cnt);
LIBBPF_API int bpf_raw_tracepoint_open(const char *name, int prog_fd);
+LIBBPF_API int bpf_raw_tracepoint_ftrace_attach(const char *subsys,
+ const char *name, int prog_fd);
+LIBBPF_API int bpf_raw_tracepoint_ftrace_detach(const char *subsys,
+ const char *name, int prog_fd);
LIBBPF_API int bpf_load_btf(void *btf, __u32 btf_size, char *log_buf,
__u32 log_buf_size, bool do_log);
LIBBPF_API int bpf_task_fd_query(int pid, int fd, __u32 flags, char *buf,
diff --git a/tools/lib/bpf/libbpf.map b/tools/lib/bpf/libbpf.map
index 673001787cba..fca377b688c2 100644
--- a/tools/lib/bpf/libbpf.map
+++ b/tools/lib/bpf/libbpf.map
@@ -163,4 +163,6 @@ LIBBPF_0.0.3 {
bpf_map__is_internal;
bpf_map_freeze;
btf__finalize_data;
+ bpf_raw_tracepoint_ftrace_attach;
+ bpf_raw_tracepoint_ftrace_detach;
} LIBBPF_0.0.2;
--
2.22.0.410.gd8fdbe21b5-goog
next prev parent reply other threads:[~2019-07-10 14:16 UTC|newest]
Thread overview: 23+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-07-10 14:15 [PATCH RFC 0/4] Add support to directly attach BPF program to ftrace Joel Fernandes (Google)
2019-07-10 14:15 ` [PATCH RFC 1/4] Move bpf_raw_tracepoint functionality into bpf_trace.c Joel Fernandes (Google)
2019-07-10 14:15 ` [PATCH RFC 2/4] trace/bpf: Add support for attach/detach of ftrace events to BPF Joel Fernandes (Google)
2019-07-10 14:15 ` Joel Fernandes (Google) [this message]
2019-07-10 14:15 ` [PATCH RFC 4/4] selftests/bpf: Add test for ftrace-based BPF attach/detach Joel Fernandes (Google)
2019-07-16 20:54 ` [PATCH RFC 0/4] Add support to directly attach BPF program to ftrace Alexei Starovoitov
2019-07-16 21:30 ` Joel Fernandes
2019-07-16 22:26 ` Alexei Starovoitov
2019-07-16 22:41 ` Joel Fernandes
2019-07-16 23:55 ` Joel Fernandes
2019-07-17 1:24 ` Alexei Starovoitov
2019-07-17 13:01 ` Joel Fernandes
2019-07-17 21:40 ` Alexei Starovoitov
2019-07-18 2:51 ` Joel Fernandes
2019-07-23 22:11 ` Alexei Starovoitov
2019-07-24 13:57 ` Joel Fernandes
2019-07-26 18:39 ` Alexei Starovoitov
2019-07-26 19:18 ` Joel Fernandes
2019-07-26 19:49 ` Joel Fernandes
2019-07-16 22:43 ` Steven Rostedt
2019-07-16 22:31 ` Steven Rostedt
2019-07-16 22:46 ` Joel Fernandes
2019-07-17 1:30 ` Alexei Starovoitov
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20190710141548.132193-4-joel@joelfernandes.org \
--to=joel@joelfernandes.org \
--cc=adrian.ratiu@collabora.com \
--cc=ast@kernel.org \
--cc=bpf@vger.kernel.org \
--cc=brendan.d.gregg@gmail.com \
--cc=carmeli.tamir@gmail.com \
--cc=connoro@google.com \
--cc=daniel@iogearbox.net \
--cc=jeffv@google.com \
--cc=kafai@fb.com \
--cc=karim.yaghmour@opersys.com \
--cc=kernel-team@android.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-kselftest@vger.kernel.org \
--cc=linux@manojrajarao.com \
--cc=manalishukla14@gmail.com \
--cc=mhiramat@kernel.org \
--cc=michalgr@fb.com \
--cc=michalgr@live.com \
--cc=mingo@redhat.com \
--cc=mmullins@fb.com \
--cc=namhyung@google.com \
--cc=namhyung@kernel.org \
--cc=netdev@vger.kernel.org \
--cc=paul.chaignon@gmail.com \
--cc=primiano@google.com \
--cc=qais.yousef@arm.com \
--cc=rostedt@goodmis.org \
--cc=russoue@gmail.com \
--cc=shuah@kernel.org \
--cc=songliubraving@fb.com \
--cc=sramana@codeaurora.org \
--cc=yhs@fb.com \
--cc=yuchao.du@unisoc.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).